An open multicenter trial of Sinemet CR in levodopa-naive Parkinson's disease patients.

It has been proposed that initiation of anti-Parkinson therapy with continuous release formulations of Sinemet might prevent or delay the development of adverse effects associated with chronic levodopa therapy employed in standard formulations. In anticipation of a prospective study comparing Sinemet to Sinemet CR in previously untreated Parkinson's disease patients, we evaluated Sinemet CR as primary therapy in 45 levodopa-naive Parkinson's disease patients in a 12 week, open-label, multi-center study. At the conclusion of the study, optimal results were obtained with levodopa administered as Sinemet CR in a total daily dose of 497 mg divided into 2.4 doses per day. Statistically significant improvement compared to baseline was observed for total Parkinson's score as well as each of rigidity, tremor, bradykinesia, gait and postural stability. Statistically significant improvement was also noted in total disability as well as in each of its components. Adverse experiences were mild and transient and no significant laboratory abnormalities were encountered. We conclude that a daily dose of 1 to 1.5 tablets b.i.d. of Sinemet CR as primary therapy for patients with Parkinson's disease is well tolerated and provides effective therapy.